Tuesday, May 18, 2010

At the oil-leak site, a tube five-feet long and four inches in diameter was pushed into a leaking riser that’s 21 inches in diameter _ the source of most of the spill. The inserted tube has three large flexible rubber diaphragms to keep it in the riser and block oil and water from mixing; however, BP officials said the riser is still leaking some oil.

The pipe is full of nitrogen, which is slowly being pulled back to let oil and gas flow in while keeping water from entering. Methanol, a kind of antifreeze, is also being pumped into the riser to stop crystals from forming that could block gas and oil from flowing to the ship. Crystals got in the way of a previous attempt to lower a 78-ton containment cap over the leak site.

The surface tanker will separate the oil, gas and water mixture for storage and eventual offloading. Overnight some of the collected gas was burned through a flare system on the tanker. BP officials weren't able to specify Sunday how much the tanker can hold.

The company says it is capturing about one fifth of the oil leaking though the pipe and hopes to raise that amount to three quarters. Meanwhile a significant amount of oil is still leaking into the gulf. It is not clear from reports exactly how many gallons are being captured and how many are still leaking. It is also not clear whether the proportions are the same whether the spill rate is closer to BP's estimate or that of independent experts. The next attempt to stop the spill will be a "top kill," which entails jamming mud and cement into the top of the well until the leak stops. That would be at best a temporary patch until a relief well is ready in August.

This study implies that the greatest risk of land impacts by surface oil caught in the Loop Current is along the ocean side of the Florida Keys, and along the coast of Southeast Florida from Miami to West Palm Beach. Eddies breaking away from the Gulf Stream would also likely bring oil to northwest Cuba, the western Bahamas, and the U.S. East Coast as far north as Cape Hatteras, North Carolina, though at lesser concentrations. Southwest Florida cannot rest entirely, though--the "forbidden zone" is only true for surface waters, and there is onshore flow below the surface. Since recent ship measurements have detected substantial plumes of oil beneath the surface, southwest Florida might be at risk if one of these plumes gets entrained into the Loop Current. ... There are plans for the Hurricane Hunters to go out again tomorrow and drop more probes into the spill to attempt to get a better handle on where the oil is and where the currents are taking it.

It is possible that some of that oil has already arrived, and a major barrier reef could be at risk. The risk to the reef is magnified if you consider that there is far more oil present underwater than is visible on the surface. BP has used massive amounts of dispersants to break up the oil leaking from the riser pipe. As a result, most of the oil is not reaching the surface.

Scientists are finding enormous oil plumes in the deep waters of the Gulf of Mexico, including one as large as 10 miles long, 3 miles wide and 300 feet thick in spots. The discovery is fresh evidence that the leak from the broken undersea well could be substantially worse than estimates that the government and BP have given.

“There’s a shocking amount of oil in the deep water, relative to what you see in the surface water,” said Samantha Joye, a researcher at the University of Georgia who is involved in one of the first scientific missions to gather details about what is happening in the gulf. “There’s a tremendous amount of oil in multiple layers, three or four or five layers deep in the water column.”

The plumes are depleting the oxygen dissolved in the gulf, worrying scientists, who fear that the oxygen level could eventually fall so low as to kill off much of the sea life near the plumes.

Dr. Joye said the oxygen had already dropped 30 percent near some of the plumes in the month that the broken oil well had been flowing. “If you keep those kinds of rates up, you could draw the oxygen down to very low levels that are dangerous to animals in a couple of months,” she said Saturday. “That is alarming.”

What this means is that underwater ecosystems are probably at far greater risk than bird nesting colonies, in either Louisiana or the Florida Keys.